Fractions


Subtracting Mixed Numbers

When Mixed Numbers are subtracted, those Mixed Numbers must first be changed to Improper Fractions.







Subtracting Mixed Numbers with Like Denominators




3
1
8

-

1
3
8




Change these Mixed Numbers to Improper Fractions.


25
8

-
11
8




To subtract these Fractions, first subtract the Numerators.

The difference of the Numerators becomes the new Numerator.

The Denominator remains the same.



25
8

-
11
8

=
14
8




If the answer results in an ImproperFraction, then change that Improper Fraction to a Mixed Number.




14
8

=

1
6
8




If the resulting Proper Fraction can be reduced, then do so.





1
6
8

=

1
3
4







Subtracting Mixed Numbers with Unlike Denominators




2
1
3

-
3
4




Change these Mixed Numbers to Improper Fractions.


7
3

-
3
4




Find the Least Common Denominator.


7
3

=
28
12



3
4

=
9
12



28
12

-
9
12




With Like Denominators, the Numerators, can be subtracted.

The difference of the Numerators becomes the new Numerator.

The Denominator remains the Least Common Denominator.



28
12

-
9
12

=
19
12




If the answer results in an ImproperFraction, then change that Improper Fraction to a Mixed Number.




19
12

=

1
7
12





RULE

Subtracting Mixed Numbers


Change the Mixed Numbers to Improper Fractions.

Change any Unlike Denominators to Like Denominators.

Subtract the Numerators. Keep the Common Denominator.

If the Proper Fraction can be Reduced, then do so.

If the answer is an Improper Fraction, then change it to a Mixed Number.